1. Field of the Invention
The present invention relates to a digital broadcasting receiver and, more particularly, to a digital broadcasting receiver which is characterized in that illegal copying is inhibited to be carried out for digital broadcasting which is copyright protected.
2. Description of the Related Art
Conventionally, when a digital broadcasting receiver displays a received video signal, if the received video signal is disallowed to be copied, the digital broadcasting receiver puts a copy-guard on an output video signal which is to be displayed.
FIG. 7 is a diagram illustrating a structure of a prior art digital broadcasting receiver. In FIG. 7, reference numeral 1 denotes a digital broadcasting receiver. Numeral 2 denotes a tuner. Numeral 3 denotes a transport decoder. Numeral 4 denotes a selector switch. Numeral 5 denotes an MPEG decoder. Numeral 6 denotes an NTSC encoder. Numeral 7 denotes a digital interface. Numeral 8 denotes copy flag information.
Hereinafter, an operation of the digital broadcasting receiver having such a conventional structure will be described.
The tuner 2 is connected to an antenna. Digital broadcasting that is received by the tuner 2 is digital-demodulated and the demodulated broadcasting is input to the transport decoder as a data sequence in the form of a transport stream. A plurality of programs and control information are multiplexed in the data sequence in the form of a transport stream. One program is selected among the plurality of programs by the transport decoder 3, and copy flag information as to whether copying to an external recording device is allowed or disallowed is separated from the data sequence in the form of a transport stream. In normal receiving, the selector switch 4 is switched to be connected to a side of the transport decoder. The program data is MPEG-decoded by the MPEG decoder 5, and a digital video image and a voice signal are output. The digital video signal among those is converted into a television signal by the NTSC encoder 6 and the television signal is output. The copy flag information 8 separated by the transport decoder 3 is connected to the digital interface 7 and the NTSC encoder 6. When the copy flag information 8 shows that copying to an external recording device is disallowed, the digital interface 7 inserts information indicating the disallowance of copying into the digital output of the program data. Further, the NTSC encoder 6 inserts a copy protect pulse into the television signal that is output from the NTSC encoder 6.
As described above, when a received video signal is disallowed to be copied to an external recording device, the prior art digital broadcasting receiver cannot record broadcasting on a VTR or the like. Therefore, a viewer is always required to view broadcasting at the instant time when the broadcasting is received.
The present invention is made in consideration of the above problems, and it is an object of the present invention to provide a digital broadcasting receiver which enables viewing the broadcasting at a time later than when the broadcasting is received, and which can satisfy a condition of disallowance of copying when the broadcasting which is disallowed to be copied is received.
In order to solve the above problems, a digital broadcasting receiver according to the present invention comprises: a tuner unit for receiving digital broadcasting information including copyright information, which shows whether copying to an external device is allowed or not, and for detecting the copyright information in the received digital broadcasting information; an information storage unit for storing the received digital broadcasting information together with the copyright information detected in the received digital broadcasting information; and a decoder unit for decoding the received digital broadcasting information or digital broadcasting information read out from the information storage unit into an output signal in a form to be displayed. When a copy-disallowance signal is detected in the digital broadcasting information read out from the information storage unit, the digital broadcasting receiver according to the present invention erases digital broadcasting information which is stored in the information storage unit and which has been successively read out therefrom during a reproduction operation in which the digital broadcasting information is read out from the information storage unit and is reproduced and displayed on a display device.
In addition, when a copy-disallowance signal included in the copyright information, which is included in the received digital broadcasting information, is detected while the received digital information is stored in the information storage unit, the digital broadcasting receiver, during receiving digital information, inhibits outputting the received digital information as an output signal in a form to be displayed through the decoder unit. Further, when a copy-disallowance signal included in the copyright information, which is included in the received digital information, is detected while the digital information is being stored in the information storage unit, the digital broadcasting receiver outputs a message screen signal, which is prepared in advance, to an output unit for outputting an output signal in a form to be displayed.
According to the present invention, even when the received video signal is one that is disallowed to be copied to an external recording device, the viewer can view broadcasting at a time later than when the broadcasting is received with the attendant copyright protection at that time being assured.
In addition, according to the present invention, in order to further assure the copyright protection, outputting of the video signal which is being received is inhibited while the digital broadcasting information which is disallowed to be copied is being stored, whereby the number of viewing times for the program under the copyright protection is limited to only one time.
A digital broadcasting receiver according to a first aspect of the present invention comprises: a tuner unit for receiving digital broadcasting information including copyright information which shows whether copying to an external device is allowed or not and detecting the copyright information included in the received digital broadcasting information; an information storage unit for storing the received digital broadcasting information together with the copyright information detected in the received digital broadcasting information; and a decoder unit for decoding the received digital broadcasting information or digital broadcasting information read out from the information storage unit into an output signal in a form to be displayed. When a copy-disallowance signal is detected in the digital broadcasting information read out from the information storage unit, the digital broadcasting receiver erases digital broadcasting information which is stored in the information storage unit and which has been successively read out therefrom during a reproduction operation for reading out the digital broadcasting information from the information storage unit and reproducing and displaying the same on a display device. Therefore, when received digital broadcasting information is disallowed to be copied to an external recording device, the received digital broadcasting information is internally and temporarily stored, and at the same time when this signal is being output, the digital broadcasting information which has been temporarily stored and successively read out, is simultaneously erased, whereby the copyright protection for the received digital broadcasting information can be realized.
According to a second aspect of the present invention, the digital broadcasting receiver of the first aspect of the present invention comprises pointer control means for controlling a reading position where information is read out from the information storage unit when digital broadcasting information is reproduced from the information storage unit. The pointer control means includes: a reading pointer for pointing to the reading position where digital broadcasting information is read out from the information storage unit, and an erasing pointer for pointing to a position where the digital broadcasting information is erased after it is read out, i.e., pointing to a position which has been pointed to by the reading pointer. Therefore, when a video signal is output, the stored video signal which has been finished in being output is simultaneously erased by utilizing an overwriting function of a storage device and a function of controlling plural pointers, whereby the copyright protection is realized.
According to a third aspect of the present invention, a digital broadcasting receiver comprises: a tuner unit for receiving digital broadcasting information including copyright information which shows whether copying to an external device is allowed or not, and for detecting the copyright information in the received digital information; an information storage unit for storing the received digital broadcasting information together with the copyright information in the received digital broadcasting information, and a decoder unit for decoding the received digital broadcasting information; or digital broadcasting information read out from the information storage unit into an output signal in a form to be displayed. When a copy-disallowance signal included in the copyright information in the received digital broadcasting information is detected while the received digital broadcasting information is stored in the information storage unit during receiving digital broadcasting information, the digital broadcasting receiver inhibits outputting the received digital broadcasting information as an output signal in a form to be displayed through the decoder unit. Therefore, the copyright protection is further reinforced.
According to a fourth aspect of the present invention, the digital broadcasting receiver of the third aspect of the present invention inhibits, when a copy-disallowance signal included in the copyright information in the received digital information is detected while the received digital broadcasting information is stored in the information storage unit, outputting the received digital broadcasting information as an output signal in a form to be displayed through the decoder unit, and outputs a message screen signal, which is prepared in advance, to an output unit for outputting an output signal in a form to be displayed through the decoder unit. Therefore, the operation for the copyright protection is further clarified.